public class Tetx1 {
    //最长公共前缀
    public String longestCommonPrefix(String[] strs) {
        if(strs==null){
            return null;
        }

        String num = strs[0];
        for(int i = 1;i<strs.length;i++ ){
            num = longest(num,strs[i]);
            if(num.length()==0){
                break;
            }
        }

        return num;
    }

    public String longest(String str1,String str2){
        int length = Math.min(str1.length(),str2.length());
        int index = 0;
        while(index<length&&str1.charAt(index)==str2.charAt(index)){
            index++;
        }

        return str1.substring(0,index);
    }

    public static void main(String[] args) {

    }
}
